A Bit About Cassin’s Auklets—Winter 2006
"Dark bird. Lighter underparts. We’re seeing lots of them," Anne Caples remarked to COASST. Hmm…we thought, not enough info to start guessing quite yet. "And these remarkable little blue feet!" Aha! A small bird with blue feet—none other than the Cassin’s Auklet.
You can really see the white crescent above the eye on this Cassin’s Auklet. (Russ Bradley)
So are these Cassin’s Auklets just a traveling road show, or a year-round attraction? It depends. Cassin’s Auklets breeding in California, Oregon and Washington are thought to stay put for the winter, but those breeding farther north (all the way into the Aleutian Islands) appear to come south for the warmer weather. Of the approximately 50 Cassin’s COASST finds each year, most occur between September and December, as worn and weary breeders make their way south.
Often mistaken for juvenile Common Murres, Cassin’s Auklets can be distinguished by their blue/gray feet, the pale spot on the base of their lower bill and white crescents above and below the eye. The juvenile murre has a proportionately longer torso, darker feet and a pale face.
Cassin's Auklet found on Pacific Beach after heavy winter storms in Northern Washington. (Ben and Flora Watson)
Like their murre cousins, these coastal breeders feed along the shelf for crustaceans and fish, using their short, stubby wings to propel them under water. They, too, are extremely sensitive to changes in the nearshore environment—during the Nestucca oil spill of 1988, Cassin’s Auklets comprised nearly 1/3 of the total recorded deaths off Vancouver Island.
Decreased upwelling this spring/early summer took its toll on more than Common Murres and Brandt’s Cormorants—unusually high numbers of Cassin’s Auklets were documented by BeachCombers (the Monterey Bay National Marine Sanctuary’s beached bird program) in January and February. Necropsies of 15 individuals showed signs of starvation. Cassin’s Auklets breeding on the Farallon Islands largely abandoned breeding for the season.
Be sure to look closely—that juvenile murre just might be a Cassin’s Auklet...
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